In this paper, we propose an energy harvesting (EH)-based spectrum access model in cognitive radio (CR) network. In the proposed scheme, one of available secondary transmitters (STs) helps a primary transmitter (PT) forward ...

In this paper outage performance of a secondary user (SU) is evaluated under amplify and forward (AF) relay selection scheme with an imperfect channel state information (CSI)while sharing spectrum in an underlay cognitive ...

Spectrum sensing is the most important process in cognitive radio in order to ensure interference avoidance to primary users. For optimal performance of cognitive radio, it is substantial to monitor and promptly react to ...

The objective of this work is to investigate the impact of noise uncertainty on the performance of a wideband spectrum segmentation technique. We define metrics to quantify the degradation due to noise uncertainty and ...

In cognitive radio techniques, OFDM is usually regarded as the physical layer candidate. However, the weaknesses of the OFDM technique, i.e., using plain FFT for spectral analysis , decreased bandwidth efficiency due to ...

The explosive growth in the use of real-time applications on mobile devices has resulted in new challenges to the design of medium access control (MAC) protocols for ad hoc networks. In this paper, we propose an energy ...

Cognitive radio arises as a hot research issue in wireless communications recently, attributed to its capability of enhancing spectral efficiency and catering for the growing demand for bandwidth. As a good embodiment of ...

In the traditional centralized cooperative spectrum sensing, all secondary users sense the same channel. But, for a given channel, there exists detection performance diversity among all the users, due to the different ...

In this paper we give an overview and a comparison of the possible waveforms for white space applications. Four physical layer schemes for cognitive radio are selected for study: Orthogonal Frequency Division Multiplexing ...

A novel integrated antenna that consists of spectrum sensing and frequency reconfigurable antenna, printed on a single substrate is presented here. The integration of both antennas is based on the fact that reasonably large ...